An Actor-Based Middleware for Crowd-Sourced Services

The growing ubiquity and variety of personal connected computational devices – each with a number of sensors – has created the opportunity for a wide range of crowd-sourced services. A busy professional could find a restaurant to go to for a quick lunch based on information available from smartphones of other people already there. Sensors on diners’ smartphones could detect whether their owners are eating, waiting to be seated, or even heading to a restaurant. Although the programming required for offering a new service of this sort is significant if done from scratch, we identify core communication mechanisms underlying such services, and implement them as part of a middleware, CSSWare. Service designers can then launch novel services over CSSWare by plugging in small pieces of service-specific code. This paper describes the multi-origin communication mechanism which we believe to underlie many crowd-sourced services. It presents our design and prototype Actor-based implementation of CSSWare, a middleware for crowd-sourced services. We present source code for two realistic crowd-sourced services to illustrate the ease with which new services can be specified and launched. Finally, we present our experimental results demonstrating scalability, performance and data-contributor side energy efficiency of the approach.